Method and apparatus for repairing leaky conduits



N i 1929. J. w. VAN DENBURG 1,736,293

METHOD AND APPARATUS FOR REPAIRING LEAKY CONDUITS Fi1ed'D .l4, 1927.

Patented Nov. 19, 19:29 I

Unites stars mum JOHN W. AN DENBTIRG, or NEW YORK, 1v: Y.

METHOD AND APPARATUS FOR REPAIRING CON DUITS Application filed December le, 1927. SerialNo. 239,891.

My invention relates to improvements in the conduit after being placed. When these methods and apparatus for repairing leaky apertures are effectively sealedagainstthe conduits and while in the broader aspect of external head or pressure, no leakage intothe invention the improvements may be apthe" conduit can take place. Obviously in a 5 plied to the repairing of conduits of many pipe or conduit of considerable length having kinds in various places, nevertheless the inan internal diameter too small to permit the vention is particularly applicable to the reentry of a' workman, it is physically impairing of underground or underwater conpractical for aworkman to seal such aper duits such assewer pipe conduits, etc., and tures by hand from the interior, and it has 10 which are too small to permit the entry of heretofore been the practice under such-air a Workman toeffect the repairs. 7 cumstances, to uncoveror raise the conduit- For example, when a sewage system is most in order to seal the apertures from the execonomicallyconstructed for a given comterior by manual operation.

munity, because of the limited capacities of The main object of'my invention is to propumping equipment, disposal facilities or vide a'method and apparatus whereby such the sewer conduits themselves, it is necesconduits may beelfectively repaired and the sary to limit the amount of infiltration or leaks sealed in a simple and eflicient manner entrance of ground Water from the exterior without digging up or uncovering any imainto the sewer conduit. It isvery frequentterial length of the conduit and by} means 20 ly found that after a sewage system or a of sealing material introduced into-the leaks 7 part" of a system has been completed, the from the inside of the conduit; Accord leakage of ground water from the exterior ingto my invention in its preferred form into the sewer conduit due todefects in maa fluent sealing material is introduced into terial or workmanship, or both, is of such the interior of a conduit or pipe line, either proportions as to seriously hinder the ef'Eecsubterranean or submarine, and forced into tive operation oflthe system, and possibly and around the outside of the leaking aperin some cases to render it practically useless tures in the walls or joints of the conduit for a period of time, thus endangering the from the interior of the conduit, under a health of the community served, or others. pressure sufiiciently greater than the head 30 When such a condition ofleakage occurred, or pressure of the liquid on the exterior of .80

the usual remedy in the case of a subterranean the conduit.) When a sufficient amount of conduit of a cross section'too small to permit the sealing material has thus been forced of workmen entering for the purpose of close into place by the excess pressure, the-presing the apertures, was to excavate or uncover sure withinthe conduitis' reduced to pthe conduit, relay. the pipe or repair the proximately that 1 of :the external pressure, 85, apertures, and back-fill again. This proceandso maintained untiltlie sealing material dure entailed a very heavy expense and great in and around the outside of the apertures inconvenience to the community. has sufiiciently s'olidified to prevent its dis- Where a leaky conduit is situatedrinwater placementby the external pressure. There 40 bearing soil or submerged under water, the after the conduit is'cleared'of the material leakage-into the conduit takes place through within audit is ready for service free of defectsin the walls or joints of the conduit, external leakage. Further objects, features and is caused by the'excess head or pressure and advantages will more clearly appear from of the'liquid on the exterior of the conduit. the detail description given-below taken .in Inthe case of a conduit made up of lengths connection with theaccompanying sheet'of of commercial sewer pipe, these defects may drawings forming a part ofthis specification. consist of apertures in the walls orjoints of In the drawings, Fig; 1 isan elevation, more the pipe, due to defective manufacture, breakor less diagrammatic, illustrating an arrangev age inhandling, imperfect workmanship in ment for carryingoutg-my improvements un sealing the joints, or unequal settlement of v a preferred ,form thereof, and Fig. 21s a lele;

vatio'n illustrating the conduit section of Fig. 1 after it liasbeen' repaired.

Referring to the draw1ngs,'3 represents a section of an underground sewer conduit composed of lengths of pipes with joints at 4, 5, 6, etc., the section of conduit extending between manholes 7 and 8, such as are usually V provided at convenient points along a sewer. As shown in Fig; 1, the conduit has leaks at at 9 forming another lea-k. 10i-ndicates' -the the joints 4 and Sand also a hole or aperture 14 represents a power pump connected tode liver't-h-e sealin'gmediuimeto, under pressure to the conduit section 3th-roughthepipe connection 11. 15 represents a tank containing a-figroutofPortland cement or other sealing material and l6wrepresents a tank or other source of water supply. The pump 14 is 7 adapted to Iwithdrawsealing material from thetank-15through pipe 17 having "a valve at 18 0iwater'froml the tank '16 through a, pipe 19 'havin'g avalveiat-20, Thus, according to.

Which-of the valves 181.0r20 is open, the pump will i deliver sealing m aterialor water to the conduit section 3Pthr0ugh the pipe cornice- V terial or 'water,;e: :'cess may flowout through V tionll. a m

I 'Wlienthe section i-sfilled with sealing ma thepipe colnnectionf12 andup through a pipe 7 turned tothest'ank 21 having avalve M22. The valve 22 being open the eXcessse'al-ing materialcwill bere- 15'through apipe 23 havingpa valve at24,or if it be water (hi C1118 being introduced into the conduit section, the

excess thereof may be returned to the tank 16 through-the pipe I25'having a valveat 26 which is open: whilejthe valve 241s closed.

Byclosing valves18,;20, 24L and-26land open a ing a valvel2'7, the fluid medium may beikept 1 1 1 8 by 'ine ans 'turned'toits'tank y a l I I also preferably provide an auxiliary hand continuously,-

circulating by 1 the pump through the conduit section without being re-7 of gwhich -vsealing medium or other fluent materia-llmay bepumped-irem a tank 29 through a pipe (having ava lve' at 31) and thencegthrou'gh theipipe connection 12 into the conduit section. represents an overflow hose -leading;fr oinithe pipe connecm al-Quad provide with -a va'lve M533. 341" represents 11a: 'pressurfe' gau'ge or "other head measuring device connected to the pipe con nection 12 and by means of which the pressure of the fluent material in the conduit section 3 may be indicated. 35 represents a valve at the outer end of the pipe connection 12. By opening this valve fluid in the conduit section 3 may be run into the next section of the seweror conduit. 1 36 represents a ValVe by means of whichthe upper end of the pipe connection 11 may be opened to the atmosphere. This may be desirable when materialis-pumpedintothe conduit section 3 by the handipum p28, or for regulating the pressure in the conduit while pump 14 is operating.

V l/Vith' the above arrangement one may proceed in several ways. I -F0I:6XL111Pl6, i2l16 grout orother sealing material may-be pumped by pump '14 fromtank 15 into the -section:3 until it is completely-filled. The valves 37;, 18,22

and 2l=will1beopen during this operation-and the valves20, 26, 27, 31, 33, 35=and 36 closed. Then 'the vaflve 22 and discharge valve 370i pump 14 maybe regulated to increase the pressure exerted by the fluid grout on the {insideofthe section 3 until-it is suifiicier'itlyin excess of the Q-external pressureedue to the water level 10to cause the grout or sealing materialto be forced into and through the leaky apertures at 4,5;and 9, thus-completely filling theseapertures and leaksand forming I exterior flIlZtSSGS ofthe sealing 'n iatei'ial-about the outside thereofas. indicated at 38, 39 "and Ogin'Fig. 2. 'Duringthis period the pressure exerted by the sealing material en -the inside of the section 3 is preferably-maintained practicallyconstant-and thesealing material is kept in constant circulation by the pump s 14, For thisfpurpose' valve -27-maybe par tially opened and valves 18- and 24 closed -:or partially; closed, ifdesired. 4 a 1 lVhen a suificient amount of the sealing material hasbeen deposited. in and around the exterior o'it'the'leaks rasat 4,5 and 9, the internal pressure isredu-cedto;approximately that of the external pressure==exerteidby the external Water and isf'so maintaineclwwhile c water -fromxthe tank 16 is pumped :in'to the 7 section- 3-by the pump-14, so that zthe excess sealiii g zmaterial' in the section 3 isgradually removed and repla'cedby the water. 'For this purpose. valve 20 "will be? opened; and. valves 18, 2a, 27,22, 31and '36will ibe maintained closed and the excess sealing material maybe allowed to escape throughthe overflow (discharge hose by regulating the valve 33- an d the elevation oi'the end oi hose 32, 1' or valve 7 35 if desiredp The operationis continued its until all of theexcess sealing material eiiiltlie conduit scction V 3-lis rep'lacedxby waters. "The discharge valve; 37 and Tvalve's "33 "and 35% are then closed and I the pinnp 146111113 downwand the pressureain the section 3 inain tained rto I balance? the external pressure by the" water maintained inthelsec tion,.is'o that the external pressure is: prevented from. .forcing the seal-.1

ing material, which has been introduced to plug the leaks, back into the conduit or away from the leaks. This condition is then continued until the grout or sealing material has set or sutficiently solidified to withstandthe external pressure. This may require from a few hoursto several days, depending onthe nature of the sealing material used and the condition of the conduit section in question. l/Vhem'however, the sealing material which has thus been introduced from theinside to plug the'leaks, has sufliciently set, valves 35, 36 and 37 may be opened and part of the water run out into the next sewer section and then pipe connections and plugs 13 may be removed, leaving the conduit section tree from leakage and without having materially reduced the efiective cross section of the con duit, and without having had to excavate about the conduit or replacing any part thereof. If desired a'quick setting cement may be used as sealing material and after it has been forced into and through the leaking apertures as above described, the body of cementin the conduit may be prevented from hardening by keepingit in circulationior/and by adding loam or other substance to the cement in the conduit to kill the same and prevent it from setting or'hardening while the cement in and outside of the leaks is hardening.

It maybe desirable as a preliminary procedure to first force .water, or a thin mixture of a: sealing material and water, by means of the pump '14 into the conduit section .3 and through the leaks and into the surroundingground toclear out the leaking apertures and where they frequently occur.

loosen the surrounding earth topermit oft thejmoreready entry and retention of the grout or sealing material of proper consist ency which may then be introduced as above described. e,

Where the system is notprovided with convenient manholes, it may be necessary to excavate at two or more suitable points in order to make the connections with the ends of the leaky section of the conduit. At times it may be desirable to shut down the pump 14 and close the valves 22 and 37 and increase orregulatethe pressure in the conduit section by operation of the auxiliaryhand pump ,to pump in either sealing material or water as thecaselmay be. W III'SOIDGj-CASQS It may be advisable to allow a small amount oilsealing materialto remain in the bottom of the conduit section as an added precaution against leakage through apertures in the bottom To secure the required stoppage, it may be necessary or desirabletocarry out the sealing procedure more than once. Where the conduitis' in use it may be necessary, durlng the progress of the repair work, to pump the fluent materialordinarily flowing through the conduit,aroundthe section being repaired or to otherwise arrange for its disposal.

In systems where manholes exist,rsuch as for example as shown in Fig. 1, advantage can be taken of themto maintain the desired pressure in the conduit section being repaired by closing off the outlets, such as at ll and 42, and filling the manholes to the proper level with Water or sealing material, or other material as the case may be, and maintaining communication between the same and the interior of the conduit 8 to secure the pressure therein-as desired. When house connections or similar branches lead off from the conduit section being repaired, it may be desirable to excavate and close them off near the main conduit while the sealing operations are in progress, suitable replacement being made after the Work has been finished, or the sealing material, etc, may be allowed to flow into such branches' and means provided to flush them out at the proper time with a suitable pressure to remove the sealing material therefrom. v. a i

From the above it will be seen that I'have provided a simple, efficient and relatively inexpensive method and apparatus for repairing subterranean and submarine conduits and a method and apparatus which is especially adapted for therepair ofleaky sewer conduits and the like which are too small to permit the entry of a workman to repair the same. The

cost is very much less than when repairs are made by other methods entailing the excavation or uncovering of long lengthsof the conduit either from the surface or by tunneling, all of which is not only expensive but difiicult, it not impracticable, in certain cases where the conduit passes through wet or difiicult ground such as quicksand,orunder water. Where the conduit lies under streets or other traveled ways, my improvements obviate the tearing up or blocking oi such thoroughfares and also permit such repair work to be done where a structure or water course above the conduit makes it difiicult or impractical to'reach the lea-ks therein from the'outside. As it is not necessary. to dig around or tear up the conduit, breakage and waste from this cause are avoided; .A comparatively small force of workmen is required as most 'ofthe work is accomplishedby me chanical means. The work can be executed rapidly and at times. when the workingarea is most available, andthe s'ame neednotbe hampered or obstructed by any of the ap 1 paratus during thetime required for the seali.

ing'material to set or solidify, since during such time the apparatus above ground may be removed. Also, delay and inconvenience caused by Waiting for back fills tojsettle, and the replacing of" paving or other structures, etcQare avoided. Also, loss of timeand'delay dueto inclement weather conditions, such as snow, trozen ground, etc, are avoided, since it is not necessary to excavate and the higher temperature ordinarily 'found in such sewer remoyin fexcess of sealing material remainfhaving its effective cross sectional area materia'lly reduced. r

as a

or similar conduitsis sufficient to permit the Work to proceed-incol'd eather. On account ofthe conduit notb'elng d sturbed", the

v possibility i of defects due to settlement aft er repair is substantially avoided. All of these objects areaccomplished by introducing a.

suitable fluent sealing material-into the. conduit and introducing and forcing the ee-me into the'leziks fromtheinterior of th'e cond'uitgafter which the'sealii'ig materialmay be to such details or forms since nianychanges and modificationsmay be made and the im vention embodied in' Widely different forms without departing from the spirit 'a-nd s'cope' ofthe improvements in their broader aspects.

Hence Idesire to cover all modifications and forms coming Within the language or scope of any one or'more of tho'appended claims. VV'hatI claim as new I and (lQSlI to secure byfLetters' Patentis:-

1. The methodof repairing leaky conduits which compr ses introducing a sealing niater'ia-l into theconduita'nd forcing it into the leaks, removing the sealing material from the IIlSldQOf the conduit befo're it sets and maintainingf sufficient gpressure 'inthe conduit to prevent'the sealing materiel hich'rem'ains at the leaks from returning into theconduit while it' is setting.

2. The method o'f repairing lealr'ingpipe conduits und'er ground or Water which are too smell 'to permit the entry ofa Work- I men therein," which comprises introducing a fluent sealing material into, the conduit un der sufficient pressure to causeit to pass into the leeks,ren oving the sealingmaterial from the ns deofthe, conduit before it sets there in and maintaining sufficient pressure in the conduit to prcventthe sealing material which remains at" the leaks from returning into the conduitwhile it is setting.

p 3. The method oflrepairing leaking pipe conduits under grounder Water which are too small'tojpermit'the entry of a Workman therein, which comprises pumping a stream of fluent sealing n'i'aterialj through the con d uitfan'd under sufficient pressure to cause to .passlinto the' leaks to close'the leaks, and

- {mg in the-conduit.

are

4. The methodof repairing leaking ,pipe' untll gmut' has A conduitsunder ground or w'at'enwhich too small toperm-it th'eentry of a worlnnan'; thereii'i,'which eomprisesintroducing a fluent sealing material, intothe conduit under sufii-i cient pressure 'to cause ,it to :jpass' intofthe' leaks',- maintaini ng the Sealing material under alesser pressure While theshme is setting and removing the excess 'sealingymaterial -frlom the inside of the conduit 'befor ezit's'ets therein;

5. The method or repairing nanngenae ground or underwater conduits yvhichcomf prises introducing a sealing material into the conduit Without removing the sameif'rom the ground or Water, the sealing material introduced under suflicient pressure toca-use it to pass into the leaks, an'd 'remou'ing the remaining sealing material from inside the conduit by the use of a circulating liquid.

6. The method of repairing, fromtheiinf-l side, leaky conduits which irresiibje'cttdiek ternal liquid'pressureand which are'too's'mall' to permit the entry of a'workman, and w'it'h out permanently-blocking the conduit "or terially "reducing its cross sectional er a, which comprises-fillin'gthe le'akin'g apertures in the conduits With a sealing material by depositing it therein under-pressure frointhe inside of: the conduit, removing the excess of the sealing material fro'mth iinside of the conduit before itsets, 'and substituting there:

for a non-setting material :to aiiitainsuifi: cie'nt pressure on the insideor the conduit to withstand the external pressure at-the leaks until the sealing material in or around the leakshas'sufiiciently setjto Withstand said a external pressure, and finally removin'g said non-setting material:

conduit which comprises plugging the aper' tu'res With sealing material depositing the same therein from the inside of the conduit and 'holding it inpl'a'ce whil'e' it i's's'etting by introducinga non setting fluent: material in the COIldllll);

The method of repairing leaky under-' ground or underwater conduits Whichare-too smallto permit the entry of'a; workman, which comprises forcing grout int the"con-- duit withsuficientjpressure toicause it topass into'the leaks and thereafter apassing'a stream' oi liquid-through the conduitto remove the excess grout and to maintainsuffi'cient pressure-upon the grout the leaks to hold'the:

same-inpl'ace during setting thereof; 9: The; method of :repairing leaky under end orgunderwaterconduits Which'a'retoo' small to perniitvthe entry j of a Workman; whicli coinprises forcinggr'eu'tinto the con-' 'duitwith suflicientpressure to causeitto pass;

into the leaks, displacingfth'e excess "of grout in theconduit WlllllL-WQJJGI and maintainingthe Water in the conduit under 'sufli'eie'nt pressure "to hold'the grout at-the leaks? inplacei 7. The method 'Of'S6al1-'I1g a ertures In a 10. -Ap'paratusfor'repairing leaky underground or underwater?conduits comprising" pipe f connections to -the" respectiv'e ends of "a section Ofillebbndlnll, meansfor closing the ends of 7 said section except for said pipe connect1ons,;and means for pumpingya seal-1,

pipe connection atone endz v 7 mg "mater a1 into the section through 11. Apparatus for repairing leaky underground or underwater conduits comprising pipe connections to the respective ends of a section of the conduit, means for closing the ends of said section except for said pipe connections, and means for pumping a sealing material into the section through the pipe connection at one end, and means whereby the excess sealing material may be removed through the pipe connection at the opposite end of the section.

12. Apparatus for repairing leaky conduits comprising pipe connections for the respective ends of a section of the conduit, a container for sealing material, a source of water supply, a pump and connections whereby the pump may pump sealing material from its container or water from said source into the section through the pipe connection at one end thereof and out through the pipe connection at the other end thereof.

13. Apparatus for repairing leaky conduits comprising pipe connections for the respective ends of a section of the conduit, a container for sealing material, a source of water supply, a pump, and connections whereby the pump may pump sealing material from its container or water from said source into the section through the pipe connection at one end thereof and out through the pipe connection at the other end thereof, and means whereby the sealing material leaving the section may be returned to its container.

14. Apparatus for repairing leaky underground or underwater conduits, comprising means for introducing a sealing material into one end of a section of the conduit and a pipe connection extending from one end of the conduit into which the sealing material may flow, whereby the sealing material may be introduced and maintained in the conduit section under pressure.

15. Apparatus for repairing leaky underground or underwater conduits, comprising means for introducing a sealing material into one end of a section of the conduit and a pipe connection extending-from the other end of the conduit into which the sealing material may flow whereby the sealing material may be introduced and maintained in the conduit section under pressure, and means connected to indicate the pressure in said conduit section.

16. The method of sealing apertures in a leaky conduit too small to permit the entry of a workman, which comprises plugging the same with sealing materials deposited under pressure from the inside of said conduit, by first forcing water through the apertures to clear said apertures and loosen surrounding medium, thereafter forcing the sealing materials through and around the outside of said apertures and holding it in place by substantially balanced pressures, until said sealing material is set.

17. The method of repairing leaking underground or underwater conduits which are too small to permit the entry of a workman therein, which comprises introducing a fluent sealing material into the conduit under sufficient pressure to cause it to pass into the leaks and then preventing the hardening of the excess fluent material in the conduit, while the sealing material in and around the leaks hardens, and then removing the material inside the conduit.

18. The method of sealing apertures in a leaky conduit too small to permit the entry of a workman, which comprises plugging the same with sealing materials deposited under pressure from the inside of said conduit, by first forcing a mixture of water and sealing material through the apertures to clear said apertures and deposit a ground work outside said apertures, thereafter forcing the sealing materials through and around the outside of said apertures and holding it in place by substantially balanced pressures, until said sealing material is set.

In testimony whereof I have signedmy name to this specification.

'W. VAN DENBURG.

JOHN

- lfIO 

